It is known to cover a security card having a passport photograph printed onto its surface by a transparent curable resin that forms a protective layer resisting removal of the photograph. The curable resin may be applied by ink jet printing in the shape of security patterns. These patterns may overlie the photograph. After printing, the resin is cured by irradiation with optical radiation, such as UV light. The known method has as a disadvantage that the printed security pattern is relatively coarse and has dimensions in the range of 1 or more mm. Furthermore, the position of a photograph on top of the top side of the security device, forms a stepped surface which may present an access point for tampering or attempted removal of the photograph. Finally, providing a resin curable layer over the photograph as a protective layer, requires application of the protective layer immediately following application of the photograph in order to prevent damaging the photograph or unauthorized alteration.
In EP 0 219 012, in particular in relation to FIG. 7, a data carrier is described in which on a base layer a colored line image is provided by printing. Over the colored line image, a cover layer is applied on top of the base layer, in which cover layer a lenticular array of cylinder lenses is formed. Via a laser, a blackened line image is interlaced in the open space between the printed line images, to form a number of distinct “flip” images that can be observed by tilting the data carrier at different angles to the viewer.
It is an object of the present invention to provide a method of forming a security document having improved security features.
It is a further object of the invention to provide a method of forming a security document having a clearly defined color portrait image.
It is another object of the present invention to provide a method of forming a security device with a portrait image below the protective layer situated below the top surface of the card.
It is a further object of the invention to provide a method of forming a security device having general security features, such as an ID card, bank card, credit card, driver's license or passport, which allows application of an image and personalization of the device at a location and time remote from the site at which general security features have been applied.